Half life number is given by n=T1 =1030=3 Nuclear of active nuclei left after n half-life is =∴==N=N0(21)n(2)34×1016=0.5×1016 Decay nuclei =N0−N4×1016−0.5×10163.5×1016
A sample of radioactive element contains 4×1016 active nuclei. The half-life of the element is 10 decays, then number of decayed nuclei after 30 days is:
Held on 30 Apr 2002 · Verified 9 Jul 2026.
0.5×1016
2×1016
3.5×1016
1×1016
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